There are numerous methods and systems for locating moveable objects such as automobiles, pets and people. One such system for locating moveable objects, such as a person, utilizes a Global Positioning Sensor (GPS) locator device that may be attached to the object, e.g., carried by the person. The GPS locator device may receive and triangulate signals from each of three or more geostationary satellites and determine the geographical coordinates of the device's current location. The geographical coordinates may be made available to an individual via a web site by the GPS locator device transmitting the GPS coordinates to either a device monitoring the GPS locator device or to a centralized location. However, GPS locator devices may not be able to receive and triangulate signals because the signals may be blocked or scattered by a variety of objects such as dense tree canopies, heavy clouds, metal roofs, layers of rock, concrete or canyon walls. For example, GPS locator devices may not be able to receive and triangulate signals in or around buildings or homes or in the woods with lots of vegetation. Hence, GPS may be of no assistance in locating an object in certain environments as discussed above. Further, in order for the GPS locator device to include both the capabilities of determining the geographical coordinates of the device's current location and transmitting that information to another device or centralized location, the GPS locator device becomes bulky and costly to implement.
One system that does not utilize GPS to locate objects, such as children, uses a monitoring device configured to monitor the position of a child by detecting the signal strength of a radio frequency carrier from a transmitter attached to the child. If the signal of the radio frequency carrier is too weak, the child is too far away from the adult who has the monitoring device. When this happens, the adult is informed that the child has wandered too far away through the use of an audio tone or through the use of vibrations coming from the device. Once the adult is notified that the child is too far away, the device also has a locating display for indicating the relative direction of the child with respect to the adult. However, since the transmitter worn by the child simply transmits a signal with no unique identification code at a particular frequency, a third party, e.g., potential abductor, may be able to intercept the signal and with a similar monitoring device track the child. Furthermore, since the transmitter worn by the child simply transmits a signal with no unique identification code at a particular frequency, a third party, e.g., potential abductor, may be able to transmit false information to the monitoring device.
Therefore, there is a need in the art for a monitoring and locating system that does not rely upon GPS and provides secure communication making it more difficult for a third party, e.g., potential abductor, potential thief, to be able to locate the object, e.g., child, automobile, as well as transmit false information to the monitoring device and/or monitored unit.